There is a lot of daylight available during the day which currently is hardly used in windowless spaces. In professional buildings in areas like washrooms, halls and stairs often artificial light is constantly burning during working hours.
Additionally it is often desired by people to have natural light wherever possible. Also, having more natural light available inter alia in hospitals is known to be welcomed by personnel as well as patients.
Several options are known where daylight is put to more effective use, such as light tubes used for transporting daylight into a building. The light tube typically has an inlet for receiving daylight at the roof of a building. The received daylight is transmitted through a pipe of the light tube to an outlet inside the building so as to illuminate the interior of the building. The resulting indoor light spot may have a shape which is dependent on the geometry of the inner light tube surface and also on the variation in sun position over a day. Thereby the diameter of the indoor light spot changes over the course of the day. To mask this dynamical spot variation at the light tube exit the arrangement is commonly fitted with one or more artificial light sources, such as LEDs, placed at the outlet of the light tube. The one or more artificial light sources may thereby enhance and/or complement the daylight whenever necessary to reach a desired light level, lighting effect or light colour. An arrangement comprising a light tube and one or more artificial light sources is commonly referred to as a hybrid arrangement.